The present invention relates generally to the art of sealed bags. More specifically, it relates to bags having a recloseable seal, such as a finger closure zipper or a slide zipper.
Resilient flexible bags, such as plastic or poly bags, are well known in the art. Some known bags include resealable or refastenable closures, such as a finger closure zipper or a slide zipper. (Finger closure zipper, as used herein, includes seals that are closed by applying pressure, such as by the user""s fingers, and squeezing together and mating the open sides of the seal or fastener strips. Slide zipper, as used herein, includes seals that are closed by sliding a closing device along the open seals that applies pressure, squeezing together and mating the open sides of the seal or fastener strips.)
Various type of bags are well known in the art, including vertical form fill seal styles of pillow bags, square bottom bags, and pre-made pouches. A vertical form fill seal bag is typically made by leading a length or strip of plastic film down over a tube with the lateral edges brought together and seamed to form a side seam, thus creating a hollow strip. If the tube is curved, the hollow strip will have a curved cross section. A cross-seam is created to form the bottom of a bag and contents are normally dropped in the bag through the tube about which the film is formed. A cross seam seals the top of the bag (which can be formed with the bottom seal of the following bag), and the filled bag is separated from the film. Pillow bags are bags with three or four seals, and the shape of the bag conforms to the material in the bag, much as a pillow case conforms its shape to the stuffing in the pillow. Pre-made pouches are bags, of any style, made prior to filling, and then filled and sealed (often at a remote location). These exemplary types of bags are well known, as are various methods and machines to make them. Known bags may be made with different types of closures, including resealable closures or non-resealable closures.
One example of a finger closure zipper on a vertical form fill seal bag is found in U.S. Pat. No. 4,840,012, entitled Zippered Film Feed, and issued Jun. 20, 1989 (incorporated herein by reference). A finger closure zipper is attached to the vertical form fill seal bags in the longitudinal (machine) direction along the full length of the bags, from the top to the bottom seals. While this type of bag allows for a side resealable closure, the zipper extends substantially the entire length of the bag, thus costing more for the zipper, and allowing for spillage of the packed material when the zipper is fully opened.
Horizontal zipper are full-length (from top to bottom seal) in the prior art because of the difficulty in apply a partial zipper. Such difficulties include registration and heating both the zippered portion and the unzippered portion to a proper temperature when sealing. Also, horizontal zippers are slide zippers in the prior art because it is difficult to apply the zipper ends and slider horizontally, (or longitudinally).
Other examples of finger closure zippers on a vertical form fill seal bags, are found in U.S. Pat. No. 4,909,017, issued Mar. 20, 1990, entitled Reclosable Bag Material, Method and Apparatus, and U.S. Pat. No. 4,655,862, entitled Method Of And Means For Making Reclosable Bags And Method Therefor, issued Apr. 7, 1987, both of which are incorporated by reference herein. These patents describe a finger closure zipper in the cross web direction. The closure is applied to the top of a bag. These patents use a zipper across the full width of the bag, and are thus not economical. Additionally, the bags described therein are not stand-up bags, i.e., when filled they do no stand on their own on a surface generally near the bottom seal.
The bags described above are not easy to pour fromxe2x80x94the resealable closure is on either the top, or all the way down the side of the bag. In either case, it is difficult to pour without spilling from such a bag when the closure is open. Also, pouring is difficult because the bags do not have handles to grasp while pouring.
U.S. Pat. No. 5,862,652, entitled Tubular Bagging Machine With An Asymmetrical Forming Shoulder And Tubular Bags With An Edge-side Longitudinal Seam Attached, issued Jan. 26, 1999 (incorporated herein by reference) shows a vertical form fills seal bag machine that produces stand-up bags. It does not show a resealable closure, in either the machine or cross directions.
Thus, a bag with a longitudinal resealable seal, that is economical and reduces the likelihood of spillage when opened is desirable. Preferably the bag will be a stand-up bag, and can be made using a wide variety of designs, and may have a handle to assist in pouring.
According to a first aspect of the invention a method of making a vertical form fill seal, stand-up, bag includes forming a hollow strip and moving the hollow strip in a vertical direction. The hollow strip is sealed, creating a horizontal bottom seal, on which the bag can stand when filled with contents. The bag is filled bag with the contents, and a top horizontal seal is made. A recloseable seal, in a direction other than horizontal, is applied to the bag. The bag is also separated from the hollow strip.
Forming the hollow strip includes forming a flexible and resilient hollow strip, and/or a plastic hollow strip in various alternative embodiments.
The recloseable seal is applied for at most a portion of the distance between the top horizontal seal and the bottom horizontal seal, or the entire distance between the top horizontal seal and the bottom horizontal seal, in other embodiments.
The recloseable seal is applied in a vertical direction, between vertical and horizontal, or horizontal in various embodiments.
A handle portion is formed above the top horizontal seal, and not filled with contents in another embodiment. Preferably, a hole is made in the handle portion.
The hollow strip is formed with a curved cross-section, and/or a cross-section with corners in other embodiments.
The hollow strip is made by sealing horizontal sides of a flat strip. The recloseable seal is applied to a portion of the strip other than the sealed horizontal sides in another embodiment.
A finger closure zipper or a slide zipper are applied in various embodiments.
A notch, extending along a length of the sealed horizontal sides is created in another embodiment. The recloseable seal is applied to the notch.
According to a second aspect of the invention a vertical form fill seal, stand-up, bag includes a hollow interior, a horizontal bottom seal located below the hollow interior and a top horizontal seal located above the hollow interior. The bag can stand, preferably on or near the bottom seal, when-filled with contents. A recloseable seal is on a perimeter of the hollow interior, and between the top and bottom seals. The recloseable seal extends in a direction other than horizontal.
The bag is further comprised of a flexible and resilient material and/or plastic in various embodiments.
The recloseable seal extends the entire distance between the top horizontal seal and the bottom horizontal seal, or at most a portion of the distance between the top horizontal seal and the bottom horizontal seal in other embodiments.
The recloseable seal extends in a vertical direction or in a direction between vertical and horizontal in various embodiments.
The bag has sealed horizontal sides and is formed from a flat strip in another embodiment. The recloseable seal is fixed to the sealed horizontal sides or to a portion of the strip other than the sealed horizontal sides.
The bag has a handle portion above the top horizontal seal in an alternative embodiment. The handle has a hole in it.
The bag has a curved cross-section, and/or a cross-section with corners in other embodiments.
The recloseable seal includes a finger closure zipper or a slide zipper in other embodiments.
The bag has sealed non-vertical sides and is formed from a flat strip in another embodiment. A notch extends along a length of the sealed sides, and the recloseable seal is fixed to the notch.
According to a third aspect of the invention a method of making a vertical form fill seal bag includes forming a hollow strip and moving the hollow strip in a vertical direction. The hollow strip is sealed to create a horizontal bottom seal and the bag is filled with contents. The hollow strip is sealed to create a top horizontal seal. A recloseable seal is applied to the bag, and the seal extends in a direction other than horizontal, and for a distance less than from the bottom seal to the top seal. The bag is separated from the hollow strip.
According to a fourth aspect of the invention a vertical form fill seal bag includes a hollow interior and a horizontal bottom seal located below the hollow interior. A top horizontal seal is located above the hollow interior. A recloseable seal extends between the top and bottom seals in a direction other than horizontal, and for a distance less than from the bottom seal to the top seal.
According to a fifth aspect of the invention a method of making a vertical form fill seal bag includes forming a hollow strip and moving the hollow strip in a vertical direction. The hollow strip is sealed on a generally horizontal line, thus creating a horizontal bottom seal. The bag is filled with contents, and a top horizontal seal is created. A recloseable seal is affixed to the bag. A handle is formed above the top horizontal-seal (and not filled with contents) and a hole is made in the handle. The bag is separated from the hollow strip.
According to a sixth aspect of the invention a vertical form fill seal bag includes a hollow interior defined by a top horizontal, a bottom horizontal seal, and side walls. A recloseable seal extends between the top and bottom seals. A handle with a hole is located above the top seal.
According to a seventh aspect of the invention a method of making a vertical form fill seal, bag includes forming a hollow strip and moving the hollow strip in a vertical direction. The hollow strip is sealed to create a horizontal bottom seal and the bag is filled with contents. The hollow strip is sealed again to create a top horizontal seal. A recloseable seal is affixed or applied to the bag in a direction other than horizontal or vertical. The bag is separated from the hollow strip.
According to an eighth aspect of the invention a vertical form fill seal, bag includes a hollow interior is defined by a horizontal bottom seal (located below the hollow interior), and a top horizontal seal located above the hollow interior. A recloseable seal extends between the top and bottom seals in a direction other than horizontal or vertical.
Other principal features and advantages of the invention will become apparent to those skilled in the art upon review of the following drawings, the detailed description and the appended claims.